Fetal presenting part other than vertex includes
breech, face, brow, transverse, and compound
presentation.
 More than one pregnancy (e.g. Multipara,Grand multipara )
 More than one fetus (e.g. Twins)
 Too much or too little amniotic fluid (e.g. Polyhydramnious,
oligohydramnios)
 Abnormal uterine shape (e.g. Arcuate ,septate, supseptate) or
abnormal growth (e.g Fibroid)
 Placenta previa
 The baby is preterm
Presentation
the part of the fetus which occupying the
lower uterine segment
Presentation may be :
(3%)
(0.5%)
Breech
Face
Brow
Shoulder
Compound
3 in 100
1 in 500
1 in 1000
1 in 300
1 in 1000
(0.3%)
Vertex 99% Face
Brow
 The occiput is in the posterior segment of pelvis,
overlying the sacroiliac joint or the sacrum
 Occipitoposterior position is responsible for most cases
of prolonged labour and second stage delay and is the
most common cause of a mobile head at term
 When the occiput is in front of the sacrum, it is termed
direct Occipitoposterior
 In the right Occipitoposterior, the occiput overlies the
right sacroiliac joint and in left Occipitoposterior, it
overlies the left sacroiliac joint
 Thus,3 positions are described –ROP, LOP, Direct
Occipitoposterior
 1. BACK ON THE RIGHT SIDE
 If the back is to the left as in 70% of vertex presentations, the
chance of a posterior position(LOP) is remote
 this is because of dextrorotation of uterus and the presence of
sigmoid colon on the left
 the foetal back is seen on the right side in 25-30% of vertex
presentations and this predisposes to occipitoposterior(ROP)
 2. ANTERIOR INSERTION OF PLACENTA
 Favours a posterior position by pushing the back of the head
with the broader biparietal diameter posteriorly
 3. SHAPE OF THE BRIM
 Influences position
 In anthropoid pelvis, the anteroposterior diameter of
the brim exceeds the transverse diameter
 This pelvis is usually of high assimilation type with an
extra vertebra in the sacrum
 Therefore, inclination of the pelvis is increased and this
favours Occipitoposterior
 In android pelvis, the inlet is wedge shaped and so the
bulky occiput cannot find space in the narrow forepelvis
 This also predisposes to Occipitoposterior
ABDOMINAL EXAMINATION
 Subumbilical flattening due to the absence of the back
anteriorly
 Back is in one or the other flank and so cannot be felt
clearly
 Limbs are felt easily anteriorly
 Shoulder is felt out in the flanks
 Unengaged or high head at term
 The sinciput and occiput may be at the same level due
to deflexion
 Fetal heart sounds are heard in the flanks and are
frequently indistinct
VAGINAL EXAMINATION
 Early in Labour
 Early rupture of conical bag of membranes
 Sagittal suture in the right oblique diameter of the
pelvis
 Smaller posterior fontanelle in the right posterior
quadrant and diamond shaped larger anterior
fontanelle in the left anterior quadrant
 As the head is deflexed, both fontanelles are easily
palpated
In occipitoanterior position, as the head is well
flexed, the posterior fontanelle will be easily
felt, but not the anterior fontanelle
On the other hand, in Occipitoposterior, the
head is usually deflexed and so the anterior
fontanelle will also be felt with ease
 LATE IN LABOUR
 A large caput may be present obscuring the sutures
 The pinna always points the occiput
 Perineum gapes much before the head distends it
and premature straining can occur
 Difficulty in applying forceps in unrecognised
occipitoposterior
Occipitoposterior position is the common
cause for prolonged labour in a vertex
presentation
The mechanism of labour will depend upon
whether the vertex is well flexed. in
occipitoposterior position with a well flexed
head, the occiput being the lower will touch the
pelvic floor first and rotate anteriorly and
labour proceeds normally
However due to the longer internal rotation in
occipitoposterior(3/8 of a circle) labour will
naturally be prolonged
In some occipitoposterior positions, the head is
deflexed and this may result in further delay in
rotation or malrotation
Deflexion may be due to when the back is
posterior, the convexity of the fetal spine abuts
against the convexity of the maternal spine causing
extension of the head
Hence large diameter present to the pelvic inlet
and the occiput is no longer the leading part. This
is also known as relative disproportion
Another problem is that in OPP, the biparietal
diameter occupies the smaller sacrocotyloid
diameter which is encroached upon by the sacral
promontory
And hence the labour is further arrested
Suboccipitofrontal diameter in a deflexed head
is 10.5cm
Occipitofrontal diameter in a head which is
further deflexed is 11.5cm
 1. Anterior rotation
 In 90% of cases, the occiput rotates anteriorly through
3/8of a circle and the baby is born as occipitoanterior.
Engagement may be delayed and labour may be longer
because of the dorsiflexion
 2. Posterior rotation and face to pubis delvery
 When the head is deflexed, the engaging diameter is the
occipitofrontal and sinciput is the leading part. Hence
the sinciput touches the pelvic floor first and rotates
anteriorly. The occiput thus rotates posteriorly into the
hollow of sacrum and delivery occurs as face to pubis.
e
B
x
i
r
t
t
e
h
n
i
s
s
i
o
b
n
yextreme flexion followed by extreme
 Perineal tears are common as the occiput is
posterior and it is the longer biparietal
diameter(9.4), which distends the perineum rather
than the smaller bitemporal(8cm). Hence liberal
episiotomy should be given.
3. Failure of rotation
 Per
rotation
sistent
and
occi
the
pitopost
head
erior is the a
b
s
e
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c
e
of
remains ROP or LOP
 Deep
ste
re
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ansve
with
rs
the
e ar
sag
rest is defined
as the head being
diameter at the level
ittal suture
in the transverse
dilatation of cervix
of
ischial spine, after full
contractions.
and in spite of
good uterine
REASONS FOR FAILURE OF ROTATION
 Deflexion of the head
 Inefficient uterine contraction
 Weak pelvic floor preventing anterior rotation
 Cephalopelvic disproportion and android
pelvis
Most of the malposition will rotate anteriorly and
the baby will be born spontaneously as occiput
anterior
Alternatively, the may rotate posteriorly and
deliver as face to pubis which need liberal
episiotomy.
As the labour is longer, judicious use of fluids and
analgesia is needed.
Epidural analgesia is ideal.
I
la
f
b
t
h
o
e
u
r
m
i
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o
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
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a
s
m
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cause is inadequate uterine action.
I
c
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ep
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a
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e
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v
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nis very useful in achieving rotation

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er
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i
c
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a
n
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o
e
p
o
r
f
ogress
even after oxytocin
1. CAESAREAN SECTION
 The pelvis should be reassessed and if the pelvis is
android or there is evidence of disproportion,
CAESAREAN SECTION should be done
 Increasing use of caesarean for deep transverse
arrest is to avoid the intracranial haemorrhage due
to traumatic vaginal delivery
2. VACCUM EXTRACTION
 This is an alternative in the absence of
cephalopelvic disproportion.
 It promotes flexion thereby reducing the diameter
presenting to the outlet from occipitofrontal to
smaller suboccipitobrgmatic.
 It is less traumatic and does not need general
anaesthesia
 The cup should be applied as near posterior
fontanelle as possible as in order to promote flexion
and smooth descent .
3. MANUAL ROTATION
 This procedure can be employed if the obstetrician
is well versed in this technique.
 Under the general anaesthesia, the right hand
grasps the sinciput displacing it thereby increasing
flexion.
 The smaller bitemporal diameter allows more space
for the thumb and finger to have a firm grasp
across the temple with middle finger on the frontal
suture. In LOP, the left hand is used. Then the
sinciput is rotated and forceps or vaccum is applied
4. FORCEPS ROTATION
 In deep transverse arrest Keilland forceps is used.
 It should be used only by the obstetrician who are
expert in its use.
 It is widely used in UK but it is not popular in India.
 Keilland forceps is applied under General
Anaesthesia in the anteroposterior direction and
rotation carried out
 This is a cephalic presentation where the attitude is one
of complete extension, presenting part is the face (area
between chin and glabella)and denominator is the chin
or mentum.
 Primary face presentation: present before the onset of
labour and are rare
 Secondary face presentation: caused by extension
during labour.( E.g. . left mentoanterior is a result of
extension of right Occipitoposterior)
The engaging diameter is submentobregmatic
9.4 cm
Maternal
 Contracted pelvis
 Oblique of uterus
 Multiparity and pendulous abdomen
Fetal
 Anencephaly and iniencephlaly
 Cord round neck
 Tumor of neck like congenital goiter
 Spasm of sternocleidomastoid muscle
 Dolichocephalic head
Abdominal examination
 In mentoanterior, back is felt with difficulty as it is
posterior and limbs are felt anteriorly
 Head remains high
 Cephalic prominence is the occiput and on the
same side as the back
 Groove between the head and back is prominent
 Fetal heart sound are transmited through the chest
and heart well anteriorly in mentoanterior
Vaginal examination
 Conrical bag of membranes
 Chin, mouth, nose, mala eminences, and
supraorbital ridges are felt
 In mentoanterior, chin is in one anterior quadrant
and forehead in the opposite posterior quadrant
Mentoanterior posterior
1. Engagement
 the engagement diameter is submentobregmatic.
In face presentation, the biparietal diameter is 7 cm
behind the face unlike in vertex, where it is only 3-4
cm distance.
 The biparietal diameter will pass through the inlet
only when the face is low down in the perineum.
When the face is distending the vulva (crowning),
the head has just engaged.
2. Descent with increasing extension
 Descent is brought by the same factors as in vertex
presentation.
 When resistance is encountered by a process of
extension, the occiput is pushed towards the back
of the fetus, while the chin descents.
3. Internal rotation
 On further descent, the chin reach
0
es the pelvic floor
and rotates anteriorly through 45 towards the
symphysis.
 Anterior rotation does not take place until the face
is well applied to the pelvic floor and may be
delayed. Only internal rotation takes place this
manner, can the neck travers the posterior surface
of the symphysis pubis.
4. flexion
 The head is born by flexion. The chin pivots under
the symphysis pubis and the mouth, nose, orbits,
forehead, vertex and occiput are born by flexion
5.Restitution and external rotation
 Restitution and external rotation of chin occurs
towards the side to which it was originally directed,
and the shoulder are born as in vertex
Mentoposterior position
2/3 of cases anteriorly through 3/8 of a circle
and deliver as mentoanterior. Of the rest, some
remain in the oblique diameter and some
rotate posteriorly into the hollow of sacrum.
In these cases of persistent mentoposterior, the
neck is too short to span the 12cm of the
anterior aspect of sacrum.
The shoulder also get impacted along with the
head making delivery impossible.
The engaging diameter is the sternobregmatic,
which is about 17cm. Hence, there is no
mechanism of labour in mentoposterior
Cause of prolonged labour in face
 Face is less effective dilator of cervix
 No moulding of face
 More chance of premature rupture of membrane
 Long internal rotation in mentoposterior
 Internal rotation occurs only late in the second
stage
complication
 prolonged and complicated labour
 Maternal distress … dehydration …
Infection
 obstructed labour → uterine rupture
 →maternal death
Fetal
complication
Rupture of fetal membranes
cord prolapse → fetal distress →fetal death
edema of the brow
marked moulding , congenital malformation
Increase in maternal and fetal morbidity and mortality
Maternal
complication
Evaluate the cephalopelvic disproportion or
other associated complication and in such
situation, caesarian section is done.
If there is no disproportion and position is
mentoanterior, labour can be allowed to
progress.
In persistent mentoposterior, cescerian section
is done.
It is the least common among cephalic
presentation and most unfavorable.
The attitude is one of partial extension , the
presenting part being the area between the
anterior fontanelle(bregma) above and the
glabella and orbital ridges bellow and
denominator is the forehead or frontum.
The presenting diameter is verticomental 13.5
cm, which is largest of fetal head
It is about 1in 1000 birth
The cause is similar to face presentation and
include any factor that interferes with flexion of
the head
Possible Etiological causes
Maternal
Fetal
BPriceomrnaatuterituyterus
SMeuplttieptleutgeersutsation
F
P
i
o
b
l
r
y
o
h
i
y
d
d
u
r
a
t
e
m
r
u
n
s
i
o
sP
Oe
lil
g
vo
ic
hy
tu
d
m
ra
o
m
r nios N
La
orn
ge
gy
F
n
e
a
te
uc
soid
pelvis Large Fetal head
Congenital Abnormalities
Cord around the neck
Neck tumor
- Left fronto-anterior.
 - Right fronto-anterior.
- Right fronto-posterior.
 - Left fronto-posterior.
Abdominal examination
 High mobile head, which feels large from side to
side
 Cephalic prominence is the occiput and is on the
same side as the back and the groove between the
cephalic prominence and the back is less prominent
than in face presentation
Vaginal examination
 Conical bag of membrane may be felt in early
labour
 Anterior fontanelle(bregma) is felt at one end and
root of nose(nasion)and orbit ridges at the other
end of an oblique or transvers diameter.
 Sometimes, the nose and the mouth are palpable,
but not the chin.
As such, ther is no mechanism of labour for
persistent brow presentation.
Spontaneous delivery is unlikely and can occur
only when there is a very small baby and large
pelvis.
In persistent brow, the verticomental diameter
is shortened and the occipitofrontal diameter is
elongated with marked moulding and a large
catput on the forehead
complication
Increase in maternal and fetal morbidity and mortality
Maternal complication
prolonged and complicated labour
Maternal distress … dehydration … keto acidosis
Infection
No engagement of presenting part
obstructed labour → uterine rupture →maternal death
fetal complication
Rupture of fetal membranes
cord prolapse → fetal distress →fetal death
marked molding
Antepartum
 It is better to wait until the onset of labour in the
hope that correction to vertex or face.
Early labour
 Cesarean section should be done. If diagnosis in
early labour before rupture of membrane, a short
period of time can be given under close supervision
in the hope of spontaneous correction.
Late labour
 It there is feature of obstructed labour, cesarean
section is performed immediately even if the fetus is
dead.
malpositionandmalpresentations-160108183858 (1).pptx

malpositionandmalpresentations-160108183858 (1).pptx

  • 2.
    Fetal presenting partother than vertex includes breech, face, brow, transverse, and compound presentation.
  • 3.
     More thanone pregnancy (e.g. Multipara,Grand multipara )  More than one fetus (e.g. Twins)  Too much or too little amniotic fluid (e.g. Polyhydramnious, oligohydramnios)  Abnormal uterine shape (e.g. Arcuate ,septate, supseptate) or abnormal growth (e.g Fibroid)  Placenta previa  The baby is preterm
  • 4.
    Presentation the part ofthe fetus which occupying the lower uterine segment Presentation may be : (3%) (0.5%) Breech Face Brow Shoulder Compound 3 in 100 1 in 500 1 in 1000 1 in 300 1 in 1000 (0.3%)
  • 6.
  • 8.
     The occiputis in the posterior segment of pelvis, overlying the sacroiliac joint or the sacrum  Occipitoposterior position is responsible for most cases of prolonged labour and second stage delay and is the most common cause of a mobile head at term  When the occiput is in front of the sacrum, it is termed direct Occipitoposterior  In the right Occipitoposterior, the occiput overlies the right sacroiliac joint and in left Occipitoposterior, it overlies the left sacroiliac joint  Thus,3 positions are described –ROP, LOP, Direct Occipitoposterior
  • 11.
     1. BACKON THE RIGHT SIDE  If the back is to the left as in 70% of vertex presentations, the chance of a posterior position(LOP) is remote  this is because of dextrorotation of uterus and the presence of sigmoid colon on the left  the foetal back is seen on the right side in 25-30% of vertex presentations and this predisposes to occipitoposterior(ROP)  2. ANTERIOR INSERTION OF PLACENTA  Favours a posterior position by pushing the back of the head with the broader biparietal diameter posteriorly
  • 12.
     3. SHAPEOF THE BRIM  Influences position  In anthropoid pelvis, the anteroposterior diameter of the brim exceeds the transverse diameter  This pelvis is usually of high assimilation type with an extra vertebra in the sacrum  Therefore, inclination of the pelvis is increased and this favours Occipitoposterior  In android pelvis, the inlet is wedge shaped and so the bulky occiput cannot find space in the narrow forepelvis  This also predisposes to Occipitoposterior
  • 13.
    ABDOMINAL EXAMINATION  Subumbilicalflattening due to the absence of the back anteriorly  Back is in one or the other flank and so cannot be felt clearly  Limbs are felt easily anteriorly  Shoulder is felt out in the flanks  Unengaged or high head at term  The sinciput and occiput may be at the same level due to deflexion  Fetal heart sounds are heard in the flanks and are frequently indistinct
  • 14.
    VAGINAL EXAMINATION  Earlyin Labour  Early rupture of conical bag of membranes  Sagittal suture in the right oblique diameter of the pelvis  Smaller posterior fontanelle in the right posterior quadrant and diamond shaped larger anterior fontanelle in the left anterior quadrant  As the head is deflexed, both fontanelles are easily palpated
  • 15.
    In occipitoanterior position,as the head is well flexed, the posterior fontanelle will be easily felt, but not the anterior fontanelle On the other hand, in Occipitoposterior, the head is usually deflexed and so the anterior fontanelle will also be felt with ease
  • 16.
     LATE INLABOUR  A large caput may be present obscuring the sutures  The pinna always points the occiput  Perineum gapes much before the head distends it and premature straining can occur  Difficulty in applying forceps in unrecognised occipitoposterior
  • 17.
    Occipitoposterior position isthe common cause for prolonged labour in a vertex presentation The mechanism of labour will depend upon whether the vertex is well flexed. in occipitoposterior position with a well flexed head, the occiput being the lower will touch the pelvic floor first and rotate anteriorly and labour proceeds normally
  • 18.
    However due tothe longer internal rotation in occipitoposterior(3/8 of a circle) labour will naturally be prolonged In some occipitoposterior positions, the head is deflexed and this may result in further delay in rotation or malrotation
  • 19.
    Deflexion may bedue to when the back is posterior, the convexity of the fetal spine abuts against the convexity of the maternal spine causing extension of the head Hence large diameter present to the pelvic inlet and the occiput is no longer the leading part. This is also known as relative disproportion Another problem is that in OPP, the biparietal diameter occupies the smaller sacrocotyloid diameter which is encroached upon by the sacral promontory And hence the labour is further arrested
  • 20.
    Suboccipitofrontal diameter ina deflexed head is 10.5cm Occipitofrontal diameter in a head which is further deflexed is 11.5cm
  • 21.
     1. Anteriorrotation  In 90% of cases, the occiput rotates anteriorly through 3/8of a circle and the baby is born as occipitoanterior. Engagement may be delayed and labour may be longer because of the dorsiflexion  2. Posterior rotation and face to pubis delvery  When the head is deflexed, the engaging diameter is the occipitofrontal and sinciput is the leading part. Hence the sinciput touches the pelvic floor first and rotates anteriorly. The occiput thus rotates posteriorly into the hollow of sacrum and delivery occurs as face to pubis. e B x i r t t e h n i s s i o b n yextreme flexion followed by extreme
  • 22.
     Perineal tearsare common as the occiput is posterior and it is the longer biparietal diameter(9.4), which distends the perineum rather than the smaller bitemporal(8cm). Hence liberal episiotomy should be given. 3. Failure of rotation  Per rotation sistent and occi the pitopost head erior is the a b s e n c e of remains ROP or LOP  Deep ste re ar tr d ansve with rs the e ar sag rest is defined as the head being diameter at the level ittal suture in the transverse dilatation of cervix of ischial spine, after full contractions. and in spite of good uterine
  • 23.
    REASONS FOR FAILUREOF ROTATION  Deflexion of the head  Inefficient uterine contraction  Weak pelvic floor preventing anterior rotation  Cephalopelvic disproportion and android pelvis
  • 24.
    Most of themalposition will rotate anteriorly and the baby will be born spontaneously as occiput anterior Alternatively, the may rotate posteriorly and deliver as face to pubis which need liberal episiotomy. As the labour is longer, judicious use of fluids and analgesia is needed. Epidural analgesia is ideal.
  • 25.
    I la f b t h o e u r m i s o t p h r e o r g a r e n s d s i b n a g b w y e a l r l, e t i h n e g re o i o s d n c o o n n e d e it d io f n or and interference.  A p r p o a g r r t e o s g s r i a s m n o a t s s a t s i s s m f a e c n t o t r i y s , e t h s s e e m n t o i a s l t a c o n m d m i f on cause is inadequateuterine action. I c n ep in h a a d lo e p q e u l a v t i e c d u i t s e p ri r n o e po ac rt t i i on, , o a x ft y e t r o e ci x n cluding a a n u d g m d e e l i n v t a e t r i y o nis very useful in achieving rotation  C c e a h e a s l a o r p e a e n l v i s c e d c t i s i o p n r o s p h o o t u i o l d n b o e r d if o th n er i e n i c s a n s o e p o r f ogress even after oxytocin
  • 26.
    1. CAESAREAN SECTION The pelvis should be reassessed and if the pelvis is android or there is evidence of disproportion, CAESAREAN SECTION should be done  Increasing use of caesarean for deep transverse arrest is to avoid the intracranial haemorrhage due to traumatic vaginal delivery
  • 27.
    2. VACCUM EXTRACTION This is an alternative in the absence of cephalopelvic disproportion.  It promotes flexion thereby reducing the diameter presenting to the outlet from occipitofrontal to smaller suboccipitobrgmatic.  It is less traumatic and does not need general anaesthesia  The cup should be applied as near posterior fontanelle as possible as in order to promote flexion and smooth descent .
  • 28.
    3. MANUAL ROTATION This procedure can be employed if the obstetrician is well versed in this technique.  Under the general anaesthesia, the right hand grasps the sinciput displacing it thereby increasing flexion.  The smaller bitemporal diameter allows more space for the thumb and finger to have a firm grasp across the temple with middle finger on the frontal suture. In LOP, the left hand is used. Then the sinciput is rotated and forceps or vaccum is applied
  • 29.
    4. FORCEPS ROTATION In deep transverse arrest Keilland forceps is used.  It should be used only by the obstetrician who are expert in its use.  It is widely used in UK but it is not popular in India.  Keilland forceps is applied under General Anaesthesia in the anteroposterior direction and rotation carried out
  • 31.
     This isa cephalic presentation where the attitude is one of complete extension, presenting part is the face (area between chin and glabella)and denominator is the chin or mentum.  Primary face presentation: present before the onset of labour and are rare  Secondary face presentation: caused by extension during labour.( E.g. . left mentoanterior is a result of extension of right Occipitoposterior)
  • 32.
    The engaging diameteris submentobregmatic 9.4 cm
  • 34.
    Maternal  Contracted pelvis Oblique of uterus  Multiparity and pendulous abdomen Fetal  Anencephaly and iniencephlaly  Cord round neck  Tumor of neck like congenital goiter  Spasm of sternocleidomastoid muscle  Dolichocephalic head
  • 35.
    Abdominal examination  Inmentoanterior, back is felt with difficulty as it is posterior and limbs are felt anteriorly  Head remains high  Cephalic prominence is the occiput and on the same side as the back  Groove between the head and back is prominent  Fetal heart sound are transmited through the chest and heart well anteriorly in mentoanterior
  • 36.
    Vaginal examination  Conricalbag of membranes  Chin, mouth, nose, mala eminences, and supraorbital ridges are felt  In mentoanterior, chin is in one anterior quadrant and forehead in the opposite posterior quadrant
  • 37.
    Mentoanterior posterior 1. Engagement the engagement diameter is submentobregmatic. In face presentation, the biparietal diameter is 7 cm behind the face unlike in vertex, where it is only 3-4 cm distance.  The biparietal diameter will pass through the inlet only when the face is low down in the perineum. When the face is distending the vulva (crowning), the head has just engaged.
  • 38.
    2. Descent withincreasing extension  Descent is brought by the same factors as in vertex presentation.  When resistance is encountered by a process of extension, the occiput is pushed towards the back of the fetus, while the chin descents.
  • 39.
    3. Internal rotation On further descent, the chin reach 0 es the pelvic floor and rotates anteriorly through 45 towards the symphysis.  Anterior rotation does not take place until the face is well applied to the pelvic floor and may be delayed. Only internal rotation takes place this manner, can the neck travers the posterior surface of the symphysis pubis.
  • 40.
    4. flexion  Thehead is born by flexion. The chin pivots under the symphysis pubis and the mouth, nose, orbits, forehead, vertex and occiput are born by flexion 5.Restitution and external rotation  Restitution and external rotation of chin occurs towards the side to which it was originally directed, and the shoulder are born as in vertex
  • 41.
    Mentoposterior position 2/3 ofcases anteriorly through 3/8 of a circle and deliver as mentoanterior. Of the rest, some remain in the oblique diameter and some rotate posteriorly into the hollow of sacrum. In these cases of persistent mentoposterior, the neck is too short to span the 12cm of the anterior aspect of sacrum.
  • 42.
    The shoulder alsoget impacted along with the head making delivery impossible. The engaging diameter is the sternobregmatic, which is about 17cm. Hence, there is no mechanism of labour in mentoposterior
  • 43.
    Cause of prolongedlabour in face  Face is less effective dilator of cervix  No moulding of face  More chance of premature rupture of membrane  Long internal rotation in mentoposterior  Internal rotation occurs only late in the second stage
  • 44.
    complication  prolonged andcomplicated labour  Maternal distress … dehydration … Infection  obstructed labour → uterine rupture  →maternal death Fetal complication Rupture of fetal membranes cord prolapse → fetal distress →fetal death edema of the brow marked moulding , congenital malformation Increase in maternal and fetal morbidity and mortality Maternal complication
  • 45.
    Evaluate the cephalopelvicdisproportion or other associated complication and in such situation, caesarian section is done. If there is no disproportion and position is mentoanterior, labour can be allowed to progress. In persistent mentoposterior, cescerian section is done.
  • 47.
    It is theleast common among cephalic presentation and most unfavorable. The attitude is one of partial extension , the presenting part being the area between the anterior fontanelle(bregma) above and the glabella and orbital ridges bellow and denominator is the forehead or frontum.
  • 48.
    The presenting diameteris verticomental 13.5 cm, which is largest of fetal head
  • 49.
    It is about1in 1000 birth The cause is similar to face presentation and include any factor that interferes with flexion of the head
  • 50.
  • 51.
    - Left fronto-anterior. - Right fronto-anterior. - Right fronto-posterior.  - Left fronto-posterior.
  • 52.
    Abdominal examination  Highmobile head, which feels large from side to side  Cephalic prominence is the occiput and is on the same side as the back and the groove between the cephalic prominence and the back is less prominent than in face presentation
  • 53.
    Vaginal examination  Conicalbag of membrane may be felt in early labour  Anterior fontanelle(bregma) is felt at one end and root of nose(nasion)and orbit ridges at the other end of an oblique or transvers diameter.  Sometimes, the nose and the mouth are palpable, but not the chin.
  • 54.
    As such, theris no mechanism of labour for persistent brow presentation. Spontaneous delivery is unlikely and can occur only when there is a very small baby and large pelvis. In persistent brow, the verticomental diameter is shortened and the occipitofrontal diameter is elongated with marked moulding and a large catput on the forehead
  • 56.
    complication Increase in maternaland fetal morbidity and mortality Maternal complication prolonged and complicated labour Maternal distress … dehydration … keto acidosis Infection No engagement of presenting part obstructed labour → uterine rupture →maternal death fetal complication Rupture of fetal membranes cord prolapse → fetal distress →fetal death marked molding
  • 57.
    Antepartum  It isbetter to wait until the onset of labour in the hope that correction to vertex or face. Early labour  Cesarean section should be done. If diagnosis in early labour before rupture of membrane, a short period of time can be given under close supervision in the hope of spontaneous correction.
  • 58.
    Late labour  Itthere is feature of obstructed labour, cesarean section is performed immediately even if the fetus is dead.